Preflight report output filenames

docs/operations.md

@@ -36,6 +36,12 @@ absolute output path and active profile, backend, model, warnings, validation,
 debug, and notification information; see the [CLI reference](cli.md) for its
 exact fields.
 
+Weatherreporter validates the final output filename before prompt inspection or
+weather collection. A valid long filename is published through a short,
+same-directory temporary sibling, so temporary naming does not shorten the
+operator-selected destination. A rejected filename does not create a missing
+parent directory.
+
 `SIGINT` and `SIGTERM` request orderly cancellation of an active action. The
 command lets cancellation and related cleanup finish before it exits; use the
 usual failed result or error to determine whether an output was published.